Coupling Matrix Extraction Technique for Auto Tuning of Highly Lossy Filters
This paper proposes a novel coupling matrix extraction technique for both highly lossy and lossless filters for the first time. Pole zero optimization is used to approximate characteristic polynomials (CP) from measured results. Coupling matrix (CM) can be derived from CP which is further used for filter auto tuning. Three different filter configurations are considered for validation of proposed CM extraction method. Finally, a lossy filter with unequal Qu tuning case is examined to demonstrate the robustness of the proposed extraction technique.